In this article, we propose a compact variable gravity compensation (CVGC) mechanism with a geometrically optimized lever shape. The CVGC mechanism can be used to generate gravity compensation torque by employing a cam and lever mechanism and can also amplify the gravity compensation torque by varying the pivot point of the lever. Among these advantages, we aimed to maximize the variable ratio of torque generation with an optimized lever. First, the mechanism concept and details of the CVGC mechanism are explained. Next, the conceptual benefit of using a curved lever instead of the original lever is explained. Afterward, the modeling and mechanics of the testbed using a curved lever are presented for force analysis. Based on these mechanics and B-spline curve representation, the methodology for optimizing the curved lever and cam profile design is presented. Finally, the performance of variable gravity compensation using the optimized lever is verified through experiments that compare the designed and measured gravity compensation torque. As we had hoped, the verification test shows that using the optimized curved lever improves the variable ratio from 5.27 to 14.43.

中文翻译：

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具有几何优化杠杆的紧凑型可变重力补偿机构，可最大程度地提高转矩产生的可变比率

在本文中，我们提出了一种具有几何优化杠杆形状的紧凑型可变重力补偿（CVGC）机制。CVGC机构可用于通过采用凸轮和杠杆机构来产生重力补偿扭矩，并且还可通过改变杠杆的枢轴点来放大重力补偿扭矩。在这些优点中，我们旨在通过优化的杠杆来最大程度地提高扭矩产生的可变比率。首先，说明CVGC机制的机制概念和细节。接下来，说明使用弯曲的杠杆代替原始杠杆的概念上的好处。随后，介绍了使用弯曲杠杆的试验台的建模和力学，以进行力分析。基于这些机制和B样条曲线表示，介绍了用于优化曲柄和凸轮轮廓设计的方法。最后，通过比较设计和测量的重力补偿扭矩的实验，验证了使用优化杠杆的可变重力补偿的性能。正如我们希望的那样，验证测试表明，使用优化的弯曲杠杆将可变比率从5.27提高到14.43。